Thermal and optical activation mechanisms of nanospring-based chemiresistors

Sensors (Basel). 2012;12(5):5608-22. doi: 10.3390/s120505608. Epub 2012 May 2.

Abstract

Chemiresistors (conductometric sensor) were fabricated on the basis of novel nanomaterials--silica nanosprings ALD coated with ZnO. The effects of high temperature and UV illumination on the electronic and gas sensing properties of chemiresistors are reported. For the thermally activated chemiresistors, a discrimination mechanism was developed and an integrated sensor-array for simultaneous real-time resistance scans was built. The integrated sensor response was tested using linear discriminant analysis (LDA). The distinguished electronic signatures of various chemical vapors were obtained at ppm level. It was found that the recovery rate at high temperature drastically increases upon UV illumination. The feasibility study of the activation method by UV illumination at room temperature was conducted.

Keywords: electronic nose; nanosprings; sensor.